编辑代码

class Main {
	public static void main(String[] args) {
        int n = 10;
		System.out.println(n + isHappy(n)?"是":"不是" + "快乐数");
    }

    public boolean isHappy(int n) {
        while(n >= 10){
            int res = 0;
            while(n > 0){
                int val = n%10;
                res += val * val;
                n /= 10;
            }
            n = res;
        }

        return (n == 1 || n == 7);
    }
}